Nerve growth factor and epidermal growth factor

In the 1950s, Rita Levi-Montalcini was interested in how the nervous system develops. She found that when she transferred mouse tumour cells into a chick embryo, it stimulated the growth of the chick’s nervous system. She realised that the tumour cells were emitting a potent signal molecule, and the biochemist Stanley Cohen assisted her in the characterisation of the nerve growth factor molecule, which we now know to be present in all animals, as it is essential for the growth and survival of nerve cells.

In mouse experiments, Cohen found that the salivary gland contained a substance that stimulated eyelid opening and tooth generation in newborn mice. He isolated the molecule – which caused the proliferation of epithelial skin cells – and called it epidermal growth factor.

Since Montalcini and Cohen’s work, many more growth factors have been discovered, giving us a far greater understanding of how complex multicellular organisms like ourselves develop, and an insight into a number of disorders of growth and maintenance, such as congenital malformations and dementia. Growth factors have great potential for use in therapies, for instance, treatments containing epidermal growth factor have been shown to enhance healing.